1. Field of the Invention
The present invention relates to an oscillation voltage stabilizing circuit. Specifically, the present invention relates to a circuit for stabilizing the oscillator voltage of an oscillation circuit of which horizontal and high voltage circuits are separately or integrally formed.
2. Discussion of Related Art
A display device consists of a horizontal oscillator circuit, horizontal drive circuit, horizontal output circuit, and horizontal deflection yoke. A flyback transformer (FBT) is used to produce a high voltage that is stabilized by a high voltage stabilizing circuit and an X-ray protection circuit.
The following patents each disclose features of the present invention but do not teach or suggest the specifically recited oscillation voltage stabilizer thereof.
U.S. Pat. No. 5,430,596 to Hamaguchi et al., entitled CRT Protector Circuit, U.S. Pat. No. 5,394,188 to Ohira, entitled High Voltage Stabilizing Circuit For Use In Color Television Receivers, U.S. Pat. No. 5,353,187 to Favreu et al., entitled Safety Circuits For A Television Receiver, and U.S. Pat. No. 5,304,898 to Kataoka et al., entitled High Voltage Generating Circuit.
Typically in contemporary practice a blocking oscillator circuit, in the form of an integrated circuit, is used for the horizontal oscillator circuit. The horizontal drive circuit supplies the base current for the horizontal output circuit to open or close an output transistor, and corrects the waveforms of the horizontal oscillation circuit. Since a pulse waveform can be utilized as a voltage to drive an output, the output can be directly driven only if the horizontal oscillator output is large enough. I have found however, that when the output circuit is used as an output load for an oscillator circuit, the oscillation frequency tends to be unstable because of large currents. Therefore, a drive circuit can be utilized as a buffer amplifier. The X-ray protection circuit stops the horizontal oscillator circuit when the output voltage generated by the FBT exceeds a predetermined limit. This circuit protects the horizontal and high voltage oscillator circuits when X-rays are excessively radiated, and when a lead wire is separated from a deflection yoke (DY). I have also noticed that since these horizontal and high voltage oscillator circuits do not have a stabilizing circuit, a high voltage or current caused by an abnormal oscillation in an output circuit results in circuit element damage.